Rewrite and redesign codegen and feature system

Also switch to somewhat proper C23 flags while we're at it.

This is a huge change. It took me forever, in between being really busy.
Sorry about that. But the good news is I'm now free to start integrating
the various patches that have accumulated since last release. Well, at
least in between still being really busy. Gotta manage expectations.

The main benefit of introducing GAMESPECIFIC() is that features
that don't apply to a particular game no longer show up *at all*, and
less time is wasted on init. It also enables a cool optimisation wherein
unnecessary REQUIRE_GAMEDATA() checks can elided at compile time
whenever the gamedata is known up-front to always exist in supported
games.

The DEF_FEAT_CVAR macro family meanwhile makes it easier to manage the
lifecycle of cvars/ccmds, with less manual registering, unhiding and
such.

Originally I was going to try and just hack these features into the
existing codegen abomination, but it just got too terrible. This rewrite
should make it easier to continue tweaking codegen behaviour in future.
It also has slightly better error messages.

1 files changed, 11 insertions, 14 deletions

diff --git a/src/fov.c b/src/fov.c
index f4b8575..2426d6e 100644
--- a/src/fov.c
+++ b/src/fov.c
@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Michael Smith <mikesmiffy128@gmail.com>
+ * Copyright © 2025 Michael Smith <mikesmiffy128@gmail.com>
  * Copyright © 2022 Willian Henrique <wsimanbrazil@yahoo.com.br>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
@@ -35,6 +35,9 @@
 #include "x86util.h"
 
 FEATURE("extended FOV range")
+// could work for other games, but generally only portal 1 people want this (the
+// rest of us consider this cheating and a problem for runs...)
+GAMESPECIFIC(Portal1)
 REQUEST(ent)
 
 DEF_CVAR_MINMAX_UNREG(fov_desired,
@@ -80,34 +83,28 @@ HANDLE_EVENT(ClientActive, struct edict *e) {
 
 static struct con_cmd *cmd_fov;
 
-PREINIT {
-	// could work for other games, but generally only portal 1 people want this
-	// (the rest of us consider this cheating and a problem for runs...)
-	return GAMETYPE_MATCHES(Portal1);
-}
-
 INIT {
 	cmd_fov = con_findcmd("fov");
-	if_cold (!cmd_fov) return false; // shouldn't happen but just in case!
+	if_cold (!cmd_fov) return FEAT_INCOMPAT; // shouldn't happen, but who knows!
 	if (real_fov_desired = con_findvar("fov_desired")) {
 		// latest steampipe already goes up to 120 fov
-		if (real_fov_desired->parent->maxval == 120) return false;
+		if (real_fov_desired->parent->maxval == 120) return FEAT_SKIP;
 		real_fov_desired->parent->maxval = 120;
 	}
 	else {
-		if (!has_ent) return false;
-		con_reg(fov_desired);
+		if (!has_ent) return FEAT_INCOMPAT;
+		con_regvar(fov_desired);
 		real_fov_desired = fov_desired;
 	}
 	if_cold (!find_SetDefaultFOV(cmd_fov)) {
 		errmsg_errorx("couldn't find SetDefaultFOV function");
-		return false;
+		return FEAT_INCOMPAT;
 	}
 	orig_SetDefaultFOV = (SetDefaultFOV_func)hook_inline(
 			(void *)orig_SetDefaultFOV, (void *)&hook_SetDefaultFOV);
 	if_cold (!orig_SetDefaultFOV) {
 		errmsg_errorsys("couldn't hook SetDefaultFOV function");
-		return false;
+		return FEAT_FAIL;
 	}
 
 	// we might not be using our cvar but simpler to do this unconditionally
@@ -115,7 +112,7 @@ INIT {
 	fov_desired->parent->base.flags &= ~CON_HIDDEN;
 	// hide the original fov command since we've effectively broken it anyway :)
 	cmd_fov->base.flags |= CON_DEVONLY;
-	return true;
+	return FEAT_OK;
 }
 
 END {